A drug delivery system (DDS) is a high-value key technology providing economic gains comparable to the development of new drugs and having a high potential of success, and it pursues an efficient medication, thereby improving the quality of patient treatment. The technique of solubilizing poorly soluble drugs, which belongs to a technique for promoting the absorption of a drug, one of the key techniques in the drug delivery system, is considered as the most reasonable way to reduce the development costs of new drug substances and at the same time increase the value of medicines currently on the market.
Meanwhile, nanocapsule technology can load the component of interest into a nano-sized capsule and then release it at a desired rate in a desired place. Capsule technology has been studied for a long time. Due to the limits in capsule size and material, technology development thereof has progressed slowly, but has recently been newly spotlighted through the development of nanocapsules integrated with nanotechnology. Such nanocapsule technology is applicable to a variety of fields including fine chemicals, medicaments, cosmetics, electronics, etc. depending on the development process of the capsule material and the type of substance to be loaded inside the capsule. In particular, in the fields of medicaments, cosmetics, etc., the nanocapsule has the potential to be variously utilized in targeted cancer therapy, drug delivery, transdermal absorption of cosmetics, imaging, etc. However, there are disadvantages in that the process of making a nanocapsule is complicated and a separate mold for forming the capsule is needed.
Affinity chromatography is a protein separation method using the affinity between a protein and a ligand (chemicals, amines, amino acids, peptides, proteins) by immobilizing the ligand having a specific interaction with the protein to be separated on a carrier. It is a selective separation method utilizing the specificity of the target protein among a variety of proteins in biological systems and has been widely used for separation and purification of fusion proteins and antibodies. In particular, IMAC (immobilized-metal affinity chromatography) is a method for purifying a protein having an affinity for a transition metal such as Ni2+, Co2+, Zn2+, etc., using a resin as a carrier, in which a ligand is coordinated to the transition metal. The metal ions such as Ni2+, Co2+, etc. have been reported to have a uniquely high affinity for the histidine tag, and a typical example of such a resin includes Ni-NTA. Nitrilotriacetic acid (NTA) is a metal chelator that forms a complex with a metal ion, and Ni-NTA forms a coordinate bond with the imidazole ring of histidine.